Prevalence of Fish Diseases in Intensively Managed Ponds in Ebonyi State

This study examined the prevalence and types of diseases affecting fish in intensively managed ponds in Ebonyi State, South East Nigeria, where aquaculture has expanded rapidly without a corresponding growth in veterinary and fish health services. Disease outbreaks represent a leading cause of production losses in Nigerian catfish aquaculture, with economic impacts magnified in intensively managed systems. Thirty intensively stocked catfish ponds in three local government areas were monitored over a five-month period. Sick and moribund fish were collected and subjected to gross pathological examination, bacteriological culture, and microscopic parasite screening. Clinical records from farm operators were also reviewed. Results revealed that bacterial infections were the most prevalent disease category, with Aeromonas hydrophila and Pseudomonas fluorescens isolated from 67 percent of diseased fish. Saprolegnia spp. fungal infections were recorded in 31 percent of ponds during the cooler months of November to January. Ectoparasite infestations, predominantly Trichodina spp. and Gyrodactylus spp., were identified in 44 percent of sampled ponds. Disease incidence was strongly correlated with high stocking density, irregular water exchange, and the absence of prophylactic health management protocols. Cumulative mortality attributed to disease was estimated at 18 percent of total stocked biomass across affected farms. The study recommends the establishment of a fish health advisory service in Ebonyi State, training of fish farmers in disease recognition, and the development of protocols for responsible antibiotic and probiotic use in aquaculture. Keywords: fish diseases, bacterial infection, aquaculture health, intensive pond culture, Ebonyi State